1,500 kg gold from discarded phones?

Source: khaleejtimes.com

Believe it or not, 1,500 kg of gold, one million kg of copper and 30,000 kg of silver can be extracted from the 100 million discarded mobile phones in China.
People’s Daily reported Thursday that about 400 million mobile phones were discarded each year, China accounting for nearly 100 million.
 According to the daily, a mobile phone has various precious materials including 0.01 percent of gold, 20-25 percent of copper and 40-50 percent of recycling plastic.
A study shows that 150 grams of gold, 100 kg of copper and 3 kg of silver can be extracted from one tonne of discarded mobile phones.
Under current situation, 100 million discarded cell phones in China weigh 10,000 tonnes.
And this would fetch a bonanza of 1,500 kg of gold, the daily said.